1. Field of the Invention
This invention relates to computing systems, and more particularly, to efficient management of resources within a semiconductor chip for an optimal combination of power reduction and high performance.
2. Description of the Relevant Art
The power consumption of modern integrated circuits (IC's) has become an increasing design issue with each generation of semiconductor chips. As power consumption increases, more costly cooling systems such as larger fans and heat sinks must be utilized in order to remove excess heat and prevent IC failure. However, cooling systems increase system costs. The IC power dissipation constraint is not only an issue for portable computers and mobile communication devices, but also for high-performance microprocessors, which may include multiple processor cores and multiple pipelines within a core.
A system-on-a-chip (SOC) integrates multiple functions into a single integrated chip substrate. The functions may include digital, analog, mixed-signal and radio-frequency (RF) functions. Typical applications are used in the area of embedded systems. Energy-constrained cellular phones, portable communication devices and entertainment audio/video (A/V) devices are some examples of systems using an SOC. An SOC may use powerful processors, whereby power consumption may significantly rise if not managed. The on-die processors may include general-purpose processors, graphics processors, application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), and so forth.
The on-die interaction of different processors and computational blocks within an integrated circuit such as an SOC may be complex and lead to inefficient communication and resource management. Power management and performance may each degrade due to these inefficiencies. In some cases, software control may be used for management of on-die resources. For example, an operating system (OS), user software, or otherwise may be used. However, software includes an inherent delay, such as tens of milliseconds, when adjusting operating modes and states of on-die resources.
In addition, software control typically focuses on individual processors, rather than the SOC in its entirety. The software control also tends to be high-level and doesn't consider low-level specifics of workloads related to a particular processor type let alone the relationships these low-level specifics have with on-die processors of different types. In one example, an OS selection policy for a power-performance state (P-state) for a given processor is based on a utilization factor. A higher utilization causes the OS policy to select a higher P-state. However, memory bounded workloads can be executed for a longer time thus creating higher utilization. Yet executing these types of workloads at a high P-state is an inefficient operation with lower performance/watt.
In view of the above, efficient methods and systems for efficient management of resources within a semiconductor chip for an improved combination of power reduction and high performance are desired.